Chemical Kinetic Simulation Of Fuel For Aero-engine Components’ Fire Test

With the development of study on fire test for aero-engine, researchers focus on the impact of the reaction mechanism for the numerical simulation of fuel combustion, which depends on the reaction mechanism whether can describe the characteristics of fuel. Due to the complex composition of aviation kerosene, it is difficult to directly acquire the reaction mechanism, and therefore researchers use alternative fuel to substitute the real fuel and obtain the reaction mechanism for the alternative fuel. Several alternative fuel have been proposed by previous studies to represent aviation kerosene Jet A being used in fire test, but none could completely describe the combustion characteristics of the components and intermediate products. With further research, the gap between the alternatives and real Jet A kerosene is constantly shrinking, and the number of species and primitive reactions involved is constantly increasing, thus numerical simulation of combustion for Jet A becomes extremely difficult. In this paper, a detailed kinetic mechanism 1st Generation, which has been proposed to alter fuels Jet A kerosene, will be in used for mechanism reduction and chemical reaction kinetics simulation, thus facilitating the numerical simulation of combustion for Jet A fuel.The study mainly includes two parts. First, to preliminarily simplify the detailed reaction mechanism, a direct relationship diagram method is used to analysis the detailed mechanism for coupling and removing the weak coupling reactions and components. Using the skeleton simplified mechanism and detailed mechanism to do numerical calculation and comparative analysis in close homogeneous batch reactor, perfect stirred reactor and premixed laminar burner-stabilized flame model.To further reduce the skeleton mechanism, sensitivity analysis and production rate analysis are used to study the key process which plays an important role in the reaction, and ultimately find a simplified mechanism containing 80 kinds of components. To verify the accuracy of the reduction results, the reduced and detailed mechanism are calculated and compared in different models. The results demonstrate the reduced mechanism combined direct relationship diagram method with sensitivity analysis was able to accurately calculate the ignition delay time, the reaction temperature, the molar fraction of reactants and major products.At last, coupling the reduction mechanism and turbulent flow to calculate the temperature and the concentration distribution of the main components in the burner model of the fire test.